a) aria trapez= (3+5)*4/2=16cm²
b)AP=x
x=2x=4
3x=4
x=4/3=AP
⇒BP=2x=8/3
c)Arie colorata=Arie trapez-ArieΔBPC-ArieΔAPD unde prin D am notat varful cu unghi ascutit al trapezului
arie colorata=16-BP*PC/2-AP*AD/2
BP*PC/2=(8/3) *3 :2=4
AP*AD/2=4/3 *5:2=10/3
arie colorata=16-4-10/3=12-10/3=(36-10)/3=26/3 cm²